The Indians called the frozen peak of this great Alaskan mountain range Denali, or 'the high one.' Most know it as Mount McKinley. This preserved wilderness comes to life with the thaw of spring and wildlife abounds during the brief summer, only to succumb to the grip of the long winter. Watch as 5-week-old grizzly cubs play, a moose gives birth to her calf, and a wood frog survives the deep freeze of winter. Breath-taking shots of dazzling northern lights over vast and lush wilderness make this an unforgettable Eden.

David Attenborough embarks on an extraordinary journey to unravel one of nature s most gripping stories the evolution of flying animals. The power of flight is one of the greatest miracles of nature. Over one hundred billion creatures soar through the air today - from nectar-drinking hummingbirds, to armoured airborne beetles; from bats hunting in the black of night, to bizarre winged lizards. The film travels back in time to unravel the astonishing 300-million-year story of how these animals first appeared, and then evolved into the huge variety of aeronauts that fill our skies today. Only now, using the latest scientific analysis, can he reveal the hidden mechanics behind their gravity-defying skills. Ground-breaking 3D cameras, high speed filming and stunning CGI bring the viewer closer than ever to this astounding aerial world.

Sir David Attenborough returns to the Galápagos Islands and travels throughout the archipelago to explain their origins and their unique fauna in evolutionary terms. He has captured a new species of pink iguana on film for the first time. In the first episode, the islands of the Galapagos rose explosively from the ocean four million years ago. Although life would not seem viable in such a remote Pacific outpost, the first arrivals landed as the fires still burned. David Attenborough explores the islands for the animals and plants that descend from these pioneers: from the sea birds carrying the seeds that made a tentative foothold on these rocks, to equator-dwelling penguins and a dancing bird with blue feet. This is a story of treacherous journeys, life-forms that forged unlikely companionships, and surviving against all odds. It is the story of an evolutionary melting pot in which anything and everything is possible.

Many argue that flying saucers and other extra-terrestrial space ships continuously visit the earth. If that were true, what kinds of technologies would such alien spacecraft require? And do eyewitness reports of UFO sightings jibe with modern theories of how interstellar travel might be possible? Authors, astronomers and theoretical physicists weigh in with the blueprints for inertia-canceling devices, nuclear-powered craft, antimatter propulsion systems and even warp drives. Based on Einstein's theories and countless scientific studies, we'll find out how these visitors might bridge the vast distances between the stars. And if they could survive such hazardous journeys, are they flesh and blood or intelligent machines?

Discover a land as exotic as it is extraordinary. Arabia offers an in-depth understanding of one of the most fascinating lifestyles and cultures. Cross the dunes with a caravan of camels, dive in the treasure-filled Red Sea, explore the ruins of the lost city of Petra, and relive the golden age of Islamic inventions. A precious land imprinted with myths and mysteries.

Experts suspect that the dinosaurs were wiped out after a city-sized asteroid smashed into the Gulf of Mexico causing a huge crater. But until now, they haven't had any proof. In a world first, evolutionary biologist Ben Garrod joins a multi-million pound drilling expedition into the exact spot the asteroid hit to get hard evidence of the link. The team overcomes huge obstacles as it attempts to drill 1,500 metres beneath sea level to pull up rock from the Chicxulub crater. Meanwhile, paleopathologist Professor Alice Roberts travels the globe meeting top scientists and gaining exclusive access to a mass fossil graveyard in New Jersey - believed to date from the same time the asteroid hit. Alice also treks by horseback across the remote plains of Patagonia, to see if the effects of the asteroid impact could have wiped out dinosaurs across the world - almost immediately.